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(No Model.) 4 Sheets-She.et 1.

A. W. 26 z. W. DAW.

ROCK DRILL.

No. 447,666. Patented Mar. 3, 1891.

(No Model.) 4 Sheets-Sheet 2.

A. w. 852. W. DAW.

ROCK DRILL.

No. 447,666. Patented Mar. 3, 1891 Q y-mw 6 m 22? {Eat @622 (No Model.) 4Sheets-Sheet3.

'A. W.-& Z. W. DAW.

ROCK DRILL.

Ila 447,666. Patented Mar. 3, 1891.

I nut; 1T0 rs,

(No Model.) 4 Sheets-Sheet 4.

A. W. 8?; Z. W. DAW.

ROCK DRILL.

N0. 447,666. Patented Mar. 6, 1891.

NITED STATES ALBERT wILLIAI'Is DAW AND ZAOHARIAS wILLIAMs DAW, or LAURVIG, NORWAY.

ROCK-DRILL.

SPECIFICATION forming part of Letters Patent No. 447,666, dated March 3, 1891. Application filed October 12, 1889. Serial No. 326,846- (No model.) Patented in England March 2, 1889, No. 3,691.

T0 at whom it may concern.-

Be it known that-we, ALBERT WILLIAMS DAW and ZACHARIAS WILLIAMS DAW, mining engineers, both subjects of the Queen of Great Britain, residing at Laurvig, in the Kingdom of Norway, have invented certain new and useful Improvements in Percussive Rock-Drills, (for which we have obtained a patent in Great Britain, No. 3,601, bearing date March 2,1889,) of which the following is a specification.

Our invention relates, first, to improvements in the class of percussive rock-drills described in the specification of our prior patent, No. 389,740, dated September 18, 1888; and it consists in an improved arrangement of the passages formed in the piston-rod for the purpose of actuating the valve of the drill-cylinder; second, to an improved arrangement of parts, enabling the same machine to be fitted to different-sized saddles, according to the length of feed desired; third, to an improved feed for advancing the drill along the saddle, and, fourth, to an improved block or bearing for fixing or combining the rotating gear and the feed-gear of the drill.

The second and third improvements are applicable to percussive rock-drills generally.

In the accompanying drawings, Figure 1 is a longitudinal-section of our improved drill. Fig. 1 is a side elevation of the end cap or cover of the valve-piston cylinders; Fig. 2, a plan of Fig. l with covers of valve-chest and pawl box removed; Fig. 3, a section through valve-chest and main cylinder on line A B; Fig. 4, a section through the rotating gear on line C D; Fig. 5, a section on line E F, showing the automatic feed-gear; Fig. 6, a plan of valve-box cover; Fig. 7, a plan of valve-box with cover removed; Fig. 8, a plan of pawl-box cover; Fig. 9, a section through G H; Fig. 10, a plan of valve; Fig. 11, a longitudinal section of saddle; Fig. 12, a plan of saddle; Fig.13,a transverse section of a saddle on line I J; Fig. 14, a transverse section of a modified form of feed-gear; Fig. 15, a horizontal section of the puppet-head of the feedgear shown, and Fig. 16 a horizontal section of a modified form of the link and pawl of such puppet-head.

In carrying out the first improvement referred to we construct the passages M M in the piston-rod R R R of such length that when the piston P is near the end of its backward stroke one end of the passage M comes outside the stuffing-box, through which such rod Works into the upper part of the cylinder, which is open to the atmosphere, while the other end of such passage M is opposite the passage M formed in the stuffing-box, and which (as described in our patent above referred to) leads to the end of the valve-cylinder 0, so that such end of-the valve-cylinder will be directly open to exhaust to the atmosphere at the time that compressed air or steam is admitted to the other end C" of such valve-cylinder in order to reverse the valve V. Similarly when the piston P is near the end of its forward stroke one end of passage M is outside the stuffing-box or open to the atmosphere, while its other end is opposite the passage M in the stuffing-box and leading to the end 0 of valve-cylinder, so that such end 0 will be directly open to exhaust to the atmosphere at the time that compressed air or steam is being admitted to the other end 0' of valve-cylinder, in order to reverse the valve V. The action described occurs ateach end of the piston-stroke, thus rendering the reversal of the valve V certain by enabling any accumulation of the motive fluid which may take place at one end of the valve-cylinder to be exhausted into the atmosphere during the action of reversing the valve V. Any suitable number of openings 0 may be made from the ends of the passages M M to the outer surface of the piston-rod. lVhen the valve-pistons P P which are connected together by stem D and between which the valve V is arranged, are caused to move in their cylinders O 0 they will carry valve V with them, and so control the movement of piston P in cylinder 0 by governing the supply and exhaust passages I I E thereof.

Our second and third improvements, which are applicable to percussive rock-drills gen erally, consist in a novel construction of parts for effecting the automatic feedor advance of the machine along the saddle as the hole is bored by the drill and which enables the same machine to be mounted on differentsized saddles, according to the length of feed required. The saddle consists of a bed I), of segmental sect ion, and having at its center the saddle-arm D by which it is connected to a carriage or column, while at each end is a vertical plate 1) These two plates D are connected together by two longitudinal bars Q, one at each side, with which four arms (3 projecting down from the drill-casing 13, engage, so that the bars serve to guide the machine in its movement in relation to the saddle. The feed-screw Q is arranged between the guide-bars Q, and is provided with a crankhandle for effecting the return movement of the machine in the usual manner after it has been automatically fed forward to the full extent on the saddle. A spring catch or pin T is arranged to fit in a suitable hole or recess in the screw, so as to prevent it rotating when the machine is being fed forward automatically. The feednntN is mounted on the feedscrew Q, and is carried in bearings forming part of or secured to the drill-casing B, in which such nut can rotate. By this arrangement, as the guide-bars Q and feed-screw Q are carried by the saddle, while the arms Q to engage the guide-bars, and the feed-nut N are carried by the machine, the latter may be mounted on any saddle, the bars and feed -screw of which may be of any desired length, but of a diameter and relative disposition suitable to engage the guidearms Q and feed-nut N on the machine. On the end of the feed-nutN a ratchet-wheel Z is attached or formed and is provided with ratchet-teeth. A puppet head or slide P has two arms J J working through guide-holes 13 in, or bearings outside, the body of the drillv casing 15, one of such arms having an opening S to receive a spring G,whieh is fitted to react against an arm II, fitting therein, and either projecting from the drill-casing or the cap used to cover the hearing. The spring G tends to force the puppet head or slide against an inclined lifter L. The puppet head or slide P has a part K, which lies in the direct path of the drill-piston rod R R as it reciproeates, and on such piston-rod R R the inclined lifter L is formed or arranged, the inclined surface acting upon the part K of the puppet-head and forcing the same outward during the backward stroke of the drill. In order to permit the drill to be rotated after each stroke, the connection between its pistonrod R and the inclined lifter L may be in the form of the swivel-joint D C or of aball or other suitable joint.

In the construction shown in Figs. ll and 16 the part of the puppethead below the lifter L has pivoted thereto a link IV, the end of which is in the form of a pawl H and shaped to engage the ratchet-teeth, which in this case are formed on the end face of the wheel Z forming part of the feed-nut N. The pivot W of the link IV extends through the puppethead, and is surrounded by a spring G tendin g to force the pawl II toward or against the ratchet-teeth. Instead of the spring G being applied to the pivot W of the link, as shown in Fig. 16, the part thereof which forms the pawl Il may be capable of sliding through the body of the link \V, and the spring G arranged to force such sliding part II. into contact with the ratchet-teeth of the feed-nut, as shown in Fig. 15. \Vhen in action the lifter L moves with the drill-spindle and piston, and accordingly raises and lowers the puppet: head I the action of the spring in the interior ot arm J thereof reacting against projecting arm H, insuring the return movement of the puppet-head during the forward stroke of the drill. The reciprocating mot-ion thus impart: ed by the drill-spindle to the puppet-head P" is communicated to the link-pawl \V, which, moreover, acquires a lateral and an angular motion in the performance of its funct ons, the former by the detent of the link sliding over the inclined planes of the teeth of the ratchetwheel Z of the feed-nut N and the latter by its being compelled to move in the circular path of the ratchet-teeth. The pivoted connection between the link Wand the puppet-head Pf, together with the spring acting upon such pivot, (or upon the sliding part working through the body of the link,) permits these movements. The teeth of the ratchet-wheel are semicircular, and the length between them is so proportioned as not to allow the pawl II. to engage the next tooth before the piston has made its full forward stroke. \Vhen this takes place, the pawl II is forced into engagement with one of such notchesor teeth by the spring G acting upon its pivot, (or upon the sliding part,) and, owing to the forward movement of the pawl which follows, a partial rotation of the ratchet-wheel Z is effected on the return or back stroke of the piston I, such movement being transmitted to the feed-nut I which turns on the feed-screw Q, and thus forces the machine forward on the saddle. In consequence of this advance the next stroke of the piston I will not be a full stroke, and will not be a full stroke again until the length of the forward movement has been bored by the drill, and until this takes place the pawl cannot enter a fresh notch or tooth of the ratchet-wheel. Immediately that: the piston regains its full stroke the pawl will engage a fresh notch or tooth anda further advance will be given to the machine. The inclined lifter L cannot rotate with the drill-spindle R R as it; is always in contact with the rubbing-surface of the puppet-head I the pressure by wh ch the surfaces are kept together by the spring G in the interior of arm J of puppet-head I being more than sufficient to counterbalance the friction of the swivel attachment D C between the lifter L and the drill-spindle R R Moreover, such rotation is entirely prevented by causing the lifter to work through the puppet-head P as shown. The lifter L is further preferably provided with guide surfaces or webs engaging suitable grooves, which serve to guide it in its to-and-fro movement with the piston-rod.

In the modified construction of feed-gear shown in Figs. 1 and 5 the arm J of the puppet-head P carries the pawl H in the guidesocket S wherein the spring G is fitted to react upon the pawl H, so as to force it in contact with the inclined planes of and (when the drill-piston has made its full stroke) to engage the teeth of the ratchet-wheel Z, secured to feed-nut N, mounted on the feedscrew Q, the teeth of such ratchet-wheel Z being in this case formed on the periphery thereof instead of on its end face, as in the arrangement previously described. The other arm J of the puppet-head or slide P has an opening S in its outer end to receive the spring G, and the arm I-I, mounted on the casing B of the drill or forming part of the cap of bearing B enters the opening S, so as to cause the reaction of spring G on the p uppet-head P as in the arrangement already described. When lifter L moves with the d rill-piston P during its back-stroke, its inclined surface forces the puppet-head P against the action of the spring G, and the pawl 11, gearing with ratchet-wheel Z, rorates the same, so as to effect the feed. During the forward stroke of the drill spring G forces the puppet-head P in the opposite direction, causing the pawl H to slip over the teeth of ratchet-wheel Z and to engage a fresh tooth thereof, when the piston again attains its full stroke in the same manner as before described.

The feed-gear can be adapted to either end of the drill. In applying the gear to the forward end of the drill a collar will be secured to the drill-piston rod, so that such collar will follow this latter in its to-and-fro movements, while permitting the piston-rod to turn within it, and to this collar the lifter L will be secured, and by its to-and-fro movements will actuate the feed-gear in the manner above described.

The fourth improvement consists in the method of providing a bearing for the end of the rifled bush Y of the rotating gear in the block or bearing F, (see Fig. 1,) and causing such block to serve as a guide for the pistonrod R and the inclined lifter L. The bearing or block F in its longitudinal. section has the block F to allow of the travel of the piston-rod R and litter L, for which it acts asa guide. The plates B at each end are accurately turned on their circular edge to fit compactly against the interior of drill-cas ing, and the whole is fixed in the position shown in Fig. 1 by screw-bolts E, (shown in Fig. 5,) one half section of each of which is in the block and the other half in casing of drill. The forward end of the rifled bush Y for rotating the drill at each backward stroke of the piston has its bearing in the rear end of the block or bearing F. I

hat we claim as our invention, and desire to secure by Letters Patent, is

1. The combination of the drill-casing, the valve-chamber connected therewith and containing the steam-valve, passages M and M connecting opposite ends of said valve-chamber with the drill-casing, a piston-rod within said casing provided with a piston P and with elongated passages M and M on opposite sides of said piston, the passage M, registering at one end with the outer atmosphere and at the other end with the passage h when the piston is near the end of its forward stroke, and the passage M registering at one end with the outer atmosphere and at the other end with the passage M when the piston is near its backward stroke,substantially as set forth.

2. The combination, in a rock-drill, of a saddle carrying the guide-bars and feed-screw, with a nut mounted to revolve in the casing of the drill and engaging the feed-screw, while arms projecting from such casing engage the guide-bars, all substantially as and for the purpose specified.

3. The combination, with the piston-rod, of

a cuneiform or wedge-shaped lifter for actuating the feed-gear, said lifter being adapted to reciprocate with the piston-rod and pre- Vented from rotating therewith, substantially as described.

4. The combination, with the drill-casing. of a hollow block F, the drill-piston-extending into said block, a lifter L, guided in said block and connected to said piston, a puppethead actuated by said litter, and a bush Y, journaled at one end in said block, substantiallyas described.

ALBERT WILLIAMS DAW. ZACHARIAS WILLIAMS DAW. Witnesses:

ANTON LORENTNER, J AS. HELMER. 

